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71.
本总结了中国首批生态博物馆的建设经验:建立生态博物馆的基本原则、发展阶段以及建设中出现的问题,对于今后我国生态博物馆的建设具有参考意义。 相似文献
72.
73.
胡占凡 《中国广播电视学刊》2005,(12):6-8
中国广播电视学会改为中国广播电视协会,是广播电视系统一件大事,如何准确地给协会定位,如何适应学会转为协会以后职能的变化,在理论上,认识上有好多问题需要解决。其中,需要重点研究的就是行业自律和行业维权。 相似文献
74.
国家军民融合战略的逐步实施对传统军工科研院所带来了冲击,同时也带来了军用技术转型升级的巨大机会.当前,我国军工科研院所广泛开展智慧院所建设,这给档案工作提出了新的要求.论文分析了智慧院所背景下企业档案工作面临的新形势,探讨了智慧院所背景下企业档案工作的发展路径,以期为智慧时代军工科研院所以及其它企业档案工作发展提供借鉴. 相似文献
75.
在新时代背景下,学术期刊作为智库研究成果的传播平台,应该加快转变自身的功能定位,并逐步探索建设智库期刊的成长之路.本文在分析新型智库特点的基础上,结合学术期刊在知识引领方面的严谨性、科学性、专业性和权威性,引入智库期刊的概念.为顺应新时代发展的要求,学术期刊不仅要发挥学术传播、交流、评价和引领的作用,更要实现服务于智库发展的功能.通过开设智库专栏、提高选题系统性、承接国家研究项目、加强期刊与期刊以及期刊与智库间的交流合作等方法,学术期刊可以逐步实现服务于智库建设的功能. 相似文献
76.
In this contribution, we develop a new approach to explore the process of knowledge transition from discovery-oriented science to technological fields, via applications-oriented research, including a mediator set. This trajectory is referred to as the D-A-T trajectory. It is shown how it can be constructed and measures are proposed to characterize the relational strength among different environments (discovery oriented research, applications-oriented research and patents) and the speed of evolution. Our approach is illustrated by a case study of three fundamental restriction enzymes articles. Among other results we found that 387 patents cited 124 of the 988 articles (a share of 12.55%) in the mediator set. Defining the non-patent references (NPR) transition rate as the number of citing patents divided by the number of articles in the mediator set yields a value 0.392. Our results suggest that the D-A-T path acts as a backbone and reveals important “invisible contributions” of an original scientific work during its evolution from discovery oriented research to outside academia. Our contribution provides a useful tool for bridging the existing gap in detecting the transition of knowledge between science and technology. 相似文献
77.
Zhigang Hu Wencan Tian Shenmeng Xu Chunbo Zhang Xianwen Wang 《Journal of Informetrics》2018,12(4):1133-1145
InCites Essential Science Indicators is becoming increasingly used to identify top-performing research and evaluate the impact of institutes. Unfortunately, our study shows that ESI indicators, as well as other normalized citation indicators, have the following flaws. First, the publication month and the online-to-print delay affect a paper’s probability of becoming a Highly Cited Paper (HCP). Papers published in the earlier months of the year are more likely to accumulate enough citation counts to rank at the top 1% compared with those published in later months of the year. Papers with longer online-to-print delays have an apparent advantage for being selected as HCPs. Research field normalizations lead to the third pitfall. Different research fields have different citation thresholds for HCPs, making research field classification important for a journal. In addition, the uniform thresholds for both articles and reviews in ESI affect the reliability of HCP selection because, on average, reviews tend to have higher citation rates than articles. ESI’s selection of HCPs provides an intuitive feel for the problems of normalized citation impact indicators, such as those provided in InCites and SciVal. 相似文献
78.
1课的设计背景(1)寒假布置学生在家制作硫酸铜大晶体,最后以提交实验报告和实验产品作为成果;(2)根据学生的作品和实验报告,评选优秀作品;(3)归纳学生在探究过程中的实验细节、感想或感受,组织学生进行发言的准备;(4)针对实验探究过程中发现的新问题,引导 相似文献
79.
Rui Li Cong Zhang Jiawen Li Yachao Zhang Shunli Liu Yanlei Hu Shaojun Jiang Chao Chen Chen Xin Yuan Tao Bin Dong Dong Wu Jiaru Chu 《国家科学评论(英文版)》2022,9(11)
Inspired by origami/kirigami, three-dimensional (3D) mesostructures assembled via a mechanics-guided approach, with reversible and maneuverable shape-morphing capabilities, have attracted great interest with regard to a broad range of applications. Despite intensive studies, the development of morphable 3D mesostructures with high-order (multi-degree-of-freedom) deformation and untethered high-frequency actuation remains challenging. This work introduces a scheme for a magnetically encoded transferable 3D mesostructure, with polyethylene terephthalate (PET) film as the skeleton and discrete magnetic domains as actuation units, to address this challenge. The high-order deformation, including hierarchical, multidirectional and blending shape morphing, is realized by encoding 3D discrete magnetization profiles on the architecture through ultraviolet curing. Reconfigurable 3D mesostructures with a modest structural modulus (∼3 GPa) enable both high-frequency (∼55 Hz) and large-deformation (∼66.8%) actuation under an alternating magnetic field. Additionally, combined with the shape-retention and adhesion property of PET, these 3D mesostructures can be readily transferred and attached to many solid substrates. On this basis, diverse functional devices, including a switchable colour letter display, liquid mixer, sequential flashlight and biomimetic sliding robot, are demonstrated to offer new perspectives for robotics and microelectronics. 相似文献
80.
Yanyao Hu Ling Fan Apparao M Rao Weijian Yu Caixiang Zhuoma Yanhong Feng Zhihui Qin Jiang Zhou Bingan Lu 《国家科学评论(英文版)》2022,9(10)
Electrolyte anions are critical for achieving high-voltage stable potassium-metal batteries (PMBs). However, the common anions cannot simultaneously prevent the formation of ‘dead K’ and the corrosion of Al current collector, resulting in poor cycling stability. Here, we demonstrate cyclic anion of hexafluoropropane-1,3-disulfonimide-based electrolytes that can mitigate the ‘dead K’ and remarkably enhance the high-voltage stability of PMBs. Particularly, even using low salt concentration (0.8 M) and additive-free carbonate-based electrolytes, the PMBs with a high-voltage polyanion cathode (4.4 V) also exhibit excellent cycling stability of 200 cycles with a good capacity retention of 83%. This noticeable electrochemical performance is due to the highly efficient passivation ability of the cyclic anions on both anode and cathode surfaces. This cyclic-anion-based electrolyte design strategy is also suitable for lithium and sodium-metal battery technologies. 相似文献